Before there was experimental data to support various contentions, it made perfect sense to believe that the likes and endorsements posted to friends on social media would drive more business. After all, didn't we all subscribe to the idea that a disgruntled customer would tell many more people about a brand's shortcomings than a happy customer would sing its praises?

Facebook has rolled out a WhatsApp update that could threaten Snapchat's share of the mobile app messaging market. The update allows WhatsApp users to share photos and videos through the app's status area. Moreover, like WhatsApp text messages, content shared through status updates is protected by end-to-end encryption -- a key distinction between WhatsApp and its competitors.

Facebook last week launched new features for advertising job openings on the network. Although many companies already have been using Facebook to find workers, the new functionality formalizes its job search capabilities, the company said. U.S. and Canadian businesses can use the company's new jobs bookmark to list open positions and allow users to apply directly from the site.

Facebook this week announced new features for News Feeds videos, along with an app for TV. News Feed videos now have sound turned on by default in mobile devices. This can be disabled in the Settings menu. A larger format to present vertical videos now is standard on iOS and Android devices. The feature became available as a preview last year. A Watch and Scroll feature lets users minimize the video they're watching and drag it to any corner of the screen.

Twitter's share price plunged 12.3 percent, closing Thursday at $16.41 after the company released its Q4 2016 financial report. It fell further on Friday, trading at $15.54 mid-day. On the bright side, daily active usage grew for the third consecutive quarter and strong growth is expected to continue, the company said. Active monthly users in Q4 totaled 319 million, up 4 percent year over year.

Twitter is once again cracking down on abusers. It has come up with new ways to prevent the creation of new abusive accounts; make search safer; and collapse potentially abusive or low-quality tweets. Twitter also pledged to persist in its anti-abuse endeavors, saying it would keep rolling out product changes, some more visible than others, and updating users on its progress.

Snap last week filed for a $3 billion IPO. The company's private market valuation is $17.8 billion, but investors reportedly have valued it at between $20 billion and $25 billion. "Twenty-five billion dollars is just nuts, but that's the market we're in," remarked Rob Enderle, principal analyst at the Enderle Group. "This could provide an opportunity for the big gambler investors," he suggested.

Googling for a Facebook customer support phone number may connect users with fraudsters. A fraudulent number reportedly appeared not only as top result in a Google search, but also as a featured snippet -- that is, highlighted in a box at the top of the search results. An investigator who called the number, posing as a Facebook customer who had been locked out of his account.

Facebook is working on a video app for set-top boxes, according to a Wednesday report. The social network wants to deliver longer-form video content -- and with it video ads -- to the living room TV, the one screen it has been unable to reach. The Facebook app soon could be available on a variety of set-top boxes, including Apple TV. The initiative reportedly began in earnest last summer, after incubating for years as a concept.

Facebook has announced that Hugo Barra will be onboarding the company to head up its virtual reality business, including the critically important Oculus team. Barra just days ago announced his departure from Xiaomi. Barra will fill the void left last month, when Brendan Iribe stepped down as CEO of Oculus to head up a new Facebook unit that will develop the PC side of its VR business.

LinkedIn has announced a new look tied to a complete overhaul of its technology architecture, which brings conversations and content front and center. The redesign brings the LinkedIn desktop in line with the mobile browser version launched in 2015. LinkedIn will roll out its new desktop globally over the next few weeks. Among the changes are a streamlined navigation bar and smarter messaging.

Google has announced three new updates to Google+ in an effort to revive interest in the faltering product. The added features will be rolled out next week, when the old Google+ layout will vanish. Lower quality comments will be hidden, although Google didn't explain how or by whom comments will be judged. Google has tweaked the Google+ UI to display more posts and less white space.

Facebook COO Sheryl Sandberg on Tuesday announced the Startup Garage, the company's first-ever business incubator, which will be located in Paris at the new Station F hub launched last year. The Startup Garage will provide a six-month program of mentorship and assistance for new companies. About10-15 data-related startup firms will occupy up to 80 desks at the Station F campus.

Facebook on Tuesday unveiled the Journalism Project, which is designed to establish stronger ties with the journalism industry. Through the project, Facebook aims to bolster the quality of journalism on the network. Among other things, the project aims to tackle the fake news issue that flared during the U.S. presidential election and its aftermath. The project will foster collaboration with news organizations.

Instagram on Wednesday announced that businesses will be able to place immersive, full-screen video ads in its Stories feature, which has attracted 150 million daily users since its launch five months ago. Further, Instagram Business Tools will include insights on stories, which will allow business users to view the reach, impressions, replies and exits for each individual story.

The frenzied 2016 election cycle mercifully is over, but Facebook's fake news problem isn't going away. The company may face steep fines in Germany if it fails to address it satisfactorily. A bill slated for consideration next year would establish fines of up to $500,000 euros per day for each day that a fake news story persisted after notification of its falsehood was provided.

Fact-checking President-elect Donald Trump can be a chore, even for people paid to do it. The Washington Post wants to make it less so, with add-ons to the popular Chrome and Firefox browsers. The browser extension, RealDonaldContext, is available from the Chrome Web Store or the Mozilla Foundation. Once installed, the extension displays any fact-checking the Post may have done.

Facebook investors have accused director Marc Andreessen of secretly coaching CEO Mark Zuckerberg regarding a major sale of shares he held. The structure of the sale enabled Zuckerberg to refocus on philanthropic activities while maintaining lifetime control over the company. The suit alleges that Andreessen secretly tipped off the CEO about concerns raised by other members of Facebook's board.

Microsoft last week closed its $26 billion acquisition of LinkedIn. LinkedIn will remain a separate company and Jeff Weiner will continue as its CEO, but he now reports to Microsoft CEO Satya Nadella. Integration of the companies' products is under way. Among many other things, a user's LinkedIn identity and network will be made available in Microsoft Outlook and the Office suite.

Many people expect celebrities and other prominent figures to have thicker skins than the average Jane or Joe. However -- as evidenced by the numbers of celebrities who've forsaken social media -- fame and fortune are not effective defenses against an all-out troll assault. While attacks on private individuals can be more personal and more targeted, they're typically much less numerous.

Facebook has teamed up with Twitter, YouTube and Microsoft to fight the proliferation of terrorist content on the Web. The tech giants will create a shared industry database of hashes for violent terrorist imagery, terrorist recruitment videos, or images they have removed from their services. They may use these shared hashes to help identify potential terrorist content on their platforms.

Twitter has purchased Yes and named the mobile app startup's CEO, Keith Coleman, as its new VP of product -- a challenging post. Coleman will be Twitter's third VP of product this year and the fifth since 2014. Twitter's main problems are monetization, which has plagued it since its founding; slowing user growth; and stiff competition. Coleman's supporters cite his previous experience at Google.

Facebook last week released six videos to educate people about artificial intelligence. AI will bring major changes to society, and will be the backbone of many of the most innovative apps and services of the future, but it remains mysterious, noted Yann LeCun, Facebook's director of AI research, and Joaquin Candela, the company's director of applied machine learning in an online post.

A few years back, when it was one company, HP made a huge mistake that cost a number of people their jobs and forced the replacement of many of its board members. The company suffered through some nasty litigation and several top executives almost landed in jail. The mistake was tied back to something called "pretexting." It also went by the more common term "identity theft."

Reddit has announced reforms designed to crack down on trolls and punish its most abusive community members. Reddit has identified hundreds of the most "toxic users," said CEO Steve Huffman, who founded the site 11 years ago while in college, and it has devised a plan to take action against them. Consequence for unacceptable behavior could range from warnings to timeouts to permanent bans.

There's an argument that it's not Facebook's job to fact-check the growing flood of fake news coming at us through its portal. After all, Facebook is just a set of pipes delivering something and is not responsible for the content. Nebulous others have that responsibility. However, Facebook is in the business of delivering content to a wide variety of people for a multitude of reasons.

Facebook has denied that its network and Messenger app were being used to spread ransomware to its users, contradicting the claims of a security firm. Two Check Point researchers last week reported they had discovered a new method for delivering malicious code to machines, which they dubbed "ImageGate." Threat actors had found a way to embed malicious code into an image, they said.

Hackers have stolen information of more than 400 million users of Friend Finder Networks, which runs several adult dating and pornography websites, LeakedSource reported. This is Friend Finders' second breach in two years. Last year, hackers accessed 4 million accounts, exposing information on users' sexual preferences and extramarital affairs. More than 412 million users were compromised.

Twitter on Tuesday suspended the account of Richard Spencer, one of the leading voices of the alt-right movement. It also expanded the use of several existing tools and changed policies to make it easier for users to fight back against abuse and harassment. Twitter suspended the accounts of Spencer, president of the National Policy Institute, a white nationalist think tank.

Facebook and Google have amended their internal policies regarding advertising on fake news posts in response to increasing pressure from users and a growing controversy within the company. There are mounting concerns that the presidential election may have been influenced by unvetted fake news stories trending on the network during the past few weeks of the cycle.